How do scientists know that the universe is expanding? The Doppler effect shows stars with red shifted light.

The Doppler effect shows stars with yellow shifted light.

The Doppler effect shows stars with blue shifted light.

The Doppler effect shows stars with green shifted light.

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.